Machine for straightening round workpieces



June 14, 1960 F. a. ABRAMSEN MACHINE FOR STRAIGHTENING ROUND WORKPIECES 2 Sheets-Sheet 1 Filed July 14, 1958 INVENTOR. Finn B. Abramsen BY w ,WL 'M HIS ATTORNEYS June 14, 1960 F. B. ABRAMSEN mcnms FOR STRAIGHTENING ROUND WORKPIECEIS Filed July 14, 1958 2 Sheets-Sheet 2 m k HH T Q. 8P m mm w w 1 mm M mm om mm 4 mi 8 m 4 W H on 1., mn W P .vm MW 3 h O mm mm mm 6% mm h H ,mm In ON Nb INVENTOR. Finn B. Abramsen HIS ATTORNEYS United States Fate-ht "me MACHINE FOR STRAIGHTENING ROUND WORKPIECES Finn B. Abramsen, 4742 Baldwin Manor Road, Pittsburgh, Pa.

Filed July 14, 1958, Ser. No. 748,300

6 Claims. (Cl. 153-108) This invention relates to machines for straightening workpieces which are round in cross section as, for example, round bars and tubes. Machines are known for straightening such workpieces, one type of such machines comprising an entrance pair of cross rolls, an exit pair of crossed rolls and an intermediate pair of crossed rolls. The workpiece to be straightened is passed successively through the passes formed by the entrance, intermediate and exit pairs of rolls. One or more motors is provided for driving the rolls of each of the pairs of rolls. The diameters of each of the rolls, when new, are equal and the driving connections from the motor to the rolls are such that the motor applies equal torque to each of the rolls.

The function of the entrance pair of rolls is to start the workpiece rotating and advance it through the straightening machine so that when the workpiece reaches the intermeidate rolls its surface speed will be substantially equal to the surface speed of the intermediate rolls. Slip between the workpiece and entrance rolls and abrasion of the entrance rolls cause excessive wear on these rolls as compared to the wear on the intermediate rolls.

The intermediate pair of rolls is required to apply straightening pressure to the workpiece and, therefore, is subject to wear but the wear on these rolls is not as drastic as that on the entrance rolls.

The exit pair of rolls is subject to the least amount of wear because the workpiece is already rotating at the correct speed when it reaches these rolls and excessive pressure is not applied at this location.

In use of a straightening machine of the known type as just described, the wear on the entrance rolls is greater than that on the intermediate rolls, which, in turn, is greater than the wear on the exit rolls. Accordingly, the diameters of the entrance rolls become smaller than the diameters of the intermediate rolls and the diameters of the intermediate rolls become smaller than those of the exit rolls. Since each of the rolls is driven at a constant speed of rotation and since all of the different pairs of rolls are in engagement with the workpiece, the rolls having the smallest diameter tend to slip more on the workpiece than the rolls of larger diameter. Because the entrance rolls after use have the smallest diameters, they tend to slip more and become abraded faster than the intermediate rolls. For similar reasons, the intermediate rolls become abraded faster than the exit rolls. Thus, in use of the prior art straightening machines, the wear on the entrance rolls is accelerated as compared with that on the intermediate rolls, which in turn, have accelerated wear as compared with that on the exit rolls. Torque is wasted by the different diameter rolls fighting each other through the drives and, therefore, more power is required in carrying out a straightening operation. Also, the wear on all the straightening machine elements, such as the bearings, shafts, drives and universal joints, becomes greater as the difierences in diameters of the different sets of rolls increase.

The present invention provides a straightening machine Patented June 14, 1960 machines. The present invention automatically compem' sates for the previously explained wear characteristics and maintains all of the rolls at substantially the same diameter. This prevents any accelerated wear which would occur when any difference in roll diameters occurs.

According to the present invention, it the machine comprises three sets of rolls, the drive motor or motors are connected so that the driving torque is transmitted directly, that is, positively, to the exit rolls, which rolls are subject to the least wear of any of the sets of rolls. The drive shafts for the intermediate rolls are in turn driven from the drive shafts for the exit rolls and the drive shafts for the entrance rolls are driven from the drive shafts for the exit or intermediate rolls. Overrunning clutches are integrally contained in the driven sprockets on the drive shafts for the intermediate and entrance rolls.

In my straightening machine, the driving torque from:

the motor means is distributed equally to all the rolls.

when the rolls are equal in diameter, as is the case with: new rolls. Any wear occurring on the entrance rolls. results in t a minute decrease in the diameters of the entrance rolls and since they are in engagement with the workpiece, they are caused to rotate a minute faster than the intermediate rolls, which faster rotation can take place due to the provision of the overrunning clutches on the drive shafts of the entrance rolls. The effect of the overrunning clutches on the entrances roll drive shafts is to minutely reduce the torque applied to these rolls until the diameter ofthe entrance rolls matches those of the exit rolls. Similar effects also occur continuously as con cerns the intermediate rolls and the exit rolls. The overall result of this action is that the diameters of the entrance and intermediate rolls are continuously matching the diameters of the exit rolls. The accelerated wear which would occur from'difierential roll diameters is eliminated. The torque which would, be wasted by different diameter rolls fighting each other'through the drives does not exist and, therefore, less power is required for straightening and there is less wear on all the machine elements, such as the bearings, shafts chains, sprockets and universal joints.

In the accompanying drawings which illustrate a preferred embodiment of my invention,

Figure 1 is a diagrammatic plan view;

Figure 2 is a section taken on the line ,lI'-II of Figure 1;

Figure 3 is a plan view on an enlarged scale, of. a portion of the machine shown in Figure l; and

Figure 4 is a sectional view on line IVIV of Figure 3.

Referring more particularly to the accompanying drawings, the machine comprises three pairs of crossed rolls,

A, B and C. The pair of rolls A comprises an upper roll 2 and a lower roll 4, the pair B comprises an upper roll 6 and a lower roll 8 and the pair C comprises anupper roll 10 and a lower roll 12. Each of the rolls has; its axis of rotation at an angle to the axis of the workpiece 14 which, in carrying out a straightening operation, moves successively through the passes formed by the rolls A, B and C in the direction indicated by the arrow. Each of the rolls has a concave workpiece engaging surface 16. The arrangement of rolls is such that the work piece is rotated as it moves forwardly through the straightening machine. The upper rolls 2, 6 and 10- are mounted A motor 22 drives the'lower rolls 12, 8 and 4 through shafts 24, 26 and 28 respectively and universal joints 25. Drive shaft 30 for roll 12 is supported in bearings 32 the inner race of overrunning clutches. The outer race 56 ofthe clutch tion. The intermediate carried by a frame 34. firive shaft 30 is driven from motor 22 by means of 'a chain 36 passing around asprocket 38 secured to motor drive shaft 40 and around :speed of rotation than the speed of rotation of the roll 12.

A drive shaft 4'8 mounted in 32 isiconneoted, by the universal joint 46'to the shaft 26 The shaft 43'is connected by a key 49'tolthe inner race 50. of an ove rrunning clutch designated generally by reference numeral 52. Cam. elements 54 are located intheannular space between 50v and an outer race 56,0f the overrunning clutch. These cam elements allow relativerotation of, the

outer race relative to the inner race in oneydirection but, prevent such relative-movement inthe other direction, all

whichisin accordance with well known characteristics is provided with teeth 58 engaged by a sprocket chain 60 which passes, around a sprocket 62 secured to the. shaft 30. I a r 1 Theshaft 28 for driving 1. 11 4 is. connected by a universal joint 64 to a shaft 66 whichlis connected by a key 67'to the inner race 68 of an overrunning clutch desig nated generallyby reference numeral?!) and having an outer face 72driven by a sprocket chain'74iwhichipasses around asprocket 76 secured tothe shaft 30. V a

Upper rolls 2, 6 and 10 are driven by a motor 22a through connections similar'to those already described connection with motor 22. Corresponding parts are, designated by the same reference numerals with an a S i c V a The invention has been described particlflarly as applied .to a straightening machinecomprising three 'setssof crossed rolls, Le, a pair of entrance rolls, a pair of exit pair of intermediate rolls in whichiall of the Although is a preferred emis not: limited tosuch construcrolls need not be driven but may or. a singleidler roll. A pair of ol s a a rolls are driving rolls. bodimen't,,,the invention beja pair of idler rolls intermediate rolls. may rollsis driven and the other is an idler rolL- The entrance, intermediate and exit pairs of rolls,=or any of them, may be replaced by sets of rolls comprising more than two rolls.

According to y invention, the driving-roll or set of driving rolls which is, subject, to the least, wear. in use of the machine is directly, that is, positively, driven. All other driving rolls are driven through overrunning clutches either directly or means for the, driving ,roll ,or-set of, driving rollswhich is subject to the least wear. V

The invention is not limited to the preferred; embodi ment but may be otherwi e embodied or practiced within the scope of the following claims. Y

I claim: a a a l. Amachine for straightening round workpieces, comprising two sets of crossed rolls, each ofsaidrollshaving; its axis of rotation at an angle to the: axis of-the workpiece,-at least one roll of eachset ofrolls being 'a driving' roll, a drive shaft for; each of said drivin'g rolls,*a rotatable straighteningdevice located; betweensaid two sets: of} crossed rolls, a drivingiroll ofone of saidse ts of 1 rolls being subject to the, le'astwear of 'eitherof said; setssof rolls when themachine isfin use, motor-means;

driving connections for driving thefdrive shaft for 7 the" driving roll least subject to wear' directly from'said motor means, 'an-overrunning clutch mounted on'the drive shaft 7 for the driving rollof said otherset ,of'rolls, and driving connections operably connected; to the drive shaft of thedriving roll least subject to wear and operable through 1- said'clutch for driving the drive shaft for the driving roll of said other set of rolls. 7

2. A machine for straighteninground workpieces, comprising two pairs of crossed rolls, each of said rolls having its axis of rotation at an angle to the axis of the workpiece, a rotatable straightening device located between said two pairs of crossed rolls, a drive shaft for each of said rolls, one pair of said rolls being subject totthe least wear of either of said pairs of rolls whenthe machine is in use, motor means, driving connections for driving the drive shafts of the'rolls least subject to wear directly from said motor means, an overrunning clutch mounted on each of the driveshafts for the other pair of rolls, and driving connections operably connected to the drive shafts of the rolls least subject to wear and operable through said clutch for driving said other pair of rolls. i

3. A machine, for s'traighteninglround workpiecen co-mprising an entrance pair of crossedrolls, an, exit pair of crossed rolls, and an intermediate pairof crossed rolls, each of said rolls having its axis of rotation at an angle to the axis of the workpiece, a drive shaft for each of said rolls, motor means, driving: connections for the drive shafts of said exit rolls directly from said motor means, an overrunning clutch mounted, on each of the drive shafts for said intermediate rolls, an overrunning clutch mounted on each of the drive shafts for said entrance rolls, and driving connections operably connected to the drive shafts for said exit rolls and operable through said clutches for driving said entrance and intermediate rolls. 7

4. A machine for straightening round workpieces, comprising three pairs of crossed rolls, each of said rolls means, driving connections for driving the drive shafts be usedin which onlyone of the i t For instance, a set of rollsmay comprise r one driven roll and one or moreidlerrolls;

indirectly, from. the, driving of the rolls least subject to wear directly from said motor means, an overrunning clutch mounted oneach' of the drive shafts for the other pairs of rolls, and idriving connections operably connected to the drive shafts of the rolls leastsubject to. wear" and, operable through. said clutches for driving the other pairs ofrollst r 5. A machine for straightening round workpieces; comprising an entrance pair of crossed rolls,'an exit pair of crossed rolls and an'intermediate pair of crossed rolls, each of said rolls havingits axisof rotation at, an angle to the axis of the workpiece, motor means, a first drive shaft operably connected to said motor means 'for driv ing one roll of said exit pair of rolls, a second drive shaft for driving one roll of saidintermediate pair of rolls, means including an overrunningclutch mounted on'said' second drive shaft-for driving said second drive shaft from said first driveshaft, a third drive shaftfor driving one roll of said entrance pair of rolls, means including an on said'third drive shaft'for from said first drive shaft, a fourth drive shaft operably connected to said motor means fordriving the other roll of I said exit pair of rolls, a fifth drive shaft for driving the other roll of said intermediate pair of rolls, means including an overrunning clutch mounted on said fifth 'drive' shaft for driving said fifth drive shaft from said fourth drive shaft, asixth driveshaft for driving the other roll ofsaid entrance pair of rolls, and. means including an'overrunning clutch mounted onsaid sixth 6. A machine for straightening round-workpieces, com;

prising an entrance pair of crossed rolls, an exit pair of crossed rolls and an intermediate pair, of crossedrolls,v

- each of said rolls having its axis of, rotation'at an angle to the axisof the workpiece, motor means, a first drive shaft operably connected to said motor means for driv-' drive shaft for driving said, sixth drive shaft from said fourth drive shaft.

shaft for driving one roll of said intermediate pair of rolls, chain and sprocket means including an overrunning clutch on said second drive shaft for driving said second drive shaft from said first drive shaft, a third drive shaft for driving one roll of said entrance pair of rolls, chain and sprocket means including an overrunning clutch on said third drive shaft for driving said third drive shaft from said first drive shaft, a fourth drive shaft operabiy connected to said motor means for driving the other roll of said exit pair of rolls, a fifth drive shaft for driving the other roll of said intermediate pair of rolls, chain and sprocket means including an over-running clutch on said fifth drive shaft for driving said fifth drive shaft from said fourth drive shaft, a sixth drive shaft for driving the other roll of said entrance pair of rolls, and chain and sprocket means including an overrunning clutch on said sixth drive shaft for driving said sixth drive shaft from said fourth drive shaft.

References Cited in the file of this patent UNITED STATES PATENTS 

